website/content/en/docs/tasks/inject-data-application/distribute-credentials-secure.md

---
title: Distribute Credentials Securely Using Secrets
content_template: templates/task
weight: 50
---

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This page shows how to securely inject sensitive data, such as passwords and
encryption keys, into Pods.
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## Convert your secret data to a base-64 representation

Suppose you want to have two pieces of secret data: a username `my-app` and a password
`39528$vdg7Jb`. First, use [Base64 encoding](https://www.base64encode.org/) to
convert your username and password to a base-64 representation. Here's a Linux
example:

```shell
echo -n 'my-app' | base64
echo -n '39528$vdg7Jb' | base64
```

The output shows that the base-64 representation of your username is `bXktYXBw`,
and the base-64 representation of your password is `Mzk1MjgkdmRnN0pi`.

## Create a Secret

Here is a configuration file you can use to create a Secret that holds your
username and password:

{{< codenew file="pods/inject/secret.yaml" >}}

1. Create the Secret

    ```shell
    kubectl apply -f https://k8s.io/examples/pods/inject/secret.yaml
    ```

1. View information about the Secret:

    ```shell
    kubectl get secret test-secret
    ```

    Output:

    ```
    NAME          TYPE      DATA      AGE
    test-secret   Opaque    2         1m
    ```

1. View more detailed information about the Secret:

    ```shell
    kubectl describe secret test-secret
    ```

    Output:

    ```
    Name:       test-secret
    Namespace:  default
    Labels:     <none>
    Annotations:    <none>

    Type:   Opaque

    Data
    ====
    password:   13 bytes
    username:   7 bytes
    ```

{{< note >}}
If you want to skip the Base64 encoding step, you can create a Secret
by using the `kubectl create secret` command:
{{< /note >}}

```shell
kubectl create secret generic test-secret --from-literal=username='my-app' --from-literal=password='39528$vdg7Jb'
```

## Create a Pod that has access to the secret data through a Volume

Here is a configuration file you can use to create a Pod:

{{< codenew file="pods/inject/secret-pod.yaml" >}}

1. Create the Pod:

    ```shell
    kubectl apply -f https://k8s.io/examples/pods/inject/secret-pod.yaml
    ```

1. Verify that your Pod is running:

    ```shell
    kubectl get pod secret-test-pod
    ```

    Output:
    ```shell
    NAME              READY     STATUS    RESTARTS   AGE
    secret-test-pod   1/1       Running   0          42m
    ```

1. Get a shell into the Container that is running in your Pod:
    ```shell
    kubectl exec -it secret-test-pod -- /bin/bash
    ```

1. The secret data is exposed to the Container through a Volume mounted under
`/etc/secret-volume`. In your shell, go to the directory where the secret data
is exposed:
    ```shell
    root@secret-test-pod:/# cd /etc/secret-volume
    ```

1. In your shell, list the files in the `/etc/secret-volume` directory:
    ```shell
    root@secret-test-pod:/etc/secret-volume# ls
    ```
    The output shows two files, one for each piece of secret data:
    ```shell
    password username
    ```

1. In your shell, display the contents of the `username` and `password` files:
    ```shell
    root@secret-test-pod:/etc/secret-volume# cat username; echo; cat password; echo
    ```
    The output is your username and password:
    ```shell
    my-app
    39528$vdg7Jb
    ```
    
## Define container environment variables using Secret data

### Define a container environment variable with data from a single Secret

*  Define an environment variable as a key-value pair in a Secret:

   ```shell
   kubectl create secret generic backend-user --from-literal=backend-username='backend-admin'
   ```

*  Assign the `backend-username` value defined in the Secret to the `SECRET_USERNAME` environment variable in the Pod specification.   
   
   {{< codenew file="pods/inject/pod-single-secret-env-variable.yaml" >}}
   
*  Create the Pod:	

   ```shell
   kubectl create -f https://k8s.io/examples/pods/inject/pod-single-secret-env-variable.yaml
   ```
   
*  Now, the Pod’s output includes environment variable `SECRET_USERNAME=backend-admin`


### Define container environment variables with data from multiple Secrets

*  As with the previous example, create the Secrets first.
  
   ```shell
     kubectl create secret generic backend-user --from-literal=backend-username='backend-admin' 
  
	 kubectl create secret generic db-user --from-literal=db-username='db-admin' 
   ```
   
*  Define the environment variables in the Pod specification.   
   
   {{< codenew file="pods/inject/pod-multiple-secret-env-variable.yaml" >}}
   
*  Create the Pod:

   ```shell
   kubectl create -f https://k8s.io/examples/pods/inject/pod-multiple-secret-env-variable.yaml 
   ```
   
*  Now, the Pod’s output includes `BACKEND_USERNAME=backend-admin` and `DB_USERNAME=db-admin` environment variables. 	 


## Configure all key-value pairs in a Secret as container environment variables

{{< note >}}
This functionality is available in Kubernetes v1.6 and later.
{{< /note >}}

*  Create a Secret containing multiple key-value pairs
   
   ```shell
   kubectl create secret generic test-secret --from-literal=username='my-app' --from-literal=password='39528$vdg7Jb'
   ```
   
*  Use envFrom to define all of the Secret’s data as container environment variables. The key from the Secret becomes the environment      variable name in the Pod.   

    {{< codenew file="pods/inject/pod-secret-envFrom.yaml" >}}
   
*  Create the Pod:

   ```shell
   kubectl create -f https://k8s.io/examples/pods/inject/pod-secret-envFrom.yaml
   ```
 
*  Now, the Pod’s output includes `username=my-app` and `password=39528$vdg7Jb` environment variables.  
   
     
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* Learn more about [Secrets](/docs/concepts/configuration/secret/).
* Learn about [Volumes](/docs/concepts/storage/volumes/).

### Reference

* [Secret](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#secret-v1-core)
* [Volume](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#volume-v1-core)
* [Pod](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#pod-v1-core)

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